New research on Japanese quake ominous for Pacific Northwest

Feb 21, 2012 By Sandi Doughton

Scientists are still unraveling last year's giant Tohoku earthquake and tsunami in Japan, and some of what they're finding doesn't bode well for the Pacific Northwest.

Detailed analyses of the way the Earth warped along the Japanese coast suggest that shaking from a Cascadia megaquake could be stronger than expected along the coasts of Washington, Oregon and British Columbia, researchers reported Sunday at the annual meeting of the American Association for the Advancement of Science.

"The Cascadia subduction zone can be seen as a mirror image of the Tohoku area," said John Anderson, of the University of Nevada.

Anderson compiled ground-motion data from the Japan quake and overlaid it on a map of the Pacific Northwest, which has a similar fault - called a subduction zone - lying offshore.

In Japan, the biggest jolts occurred underwater. The seafloor was displaced by 150 feet or more in some places, triggering the massive tsunami. But in the Northwest, it's the land that will be rocked hardest - because the Pacific coast here lies so close to the subduction zone.

"The ground motions that we have from Tohoku may actually be an indication that there could be much stronger shaking in the coastal areas of British Columbia, Washington and Oregon," Anderson said.

Cities like Seattle, Portland and Vancouver, B.C., are far enough from the coast that they might dodge the most violent hammering. But all of the urban areas sit on geologic basins that can amplify ground motion like waves in a bathtub.

"Basins shake more than hard rock," Anderson said. "Local site conditions can have an enormous effect on the nature of strong ground motions."

The U.S. Geological Survey (USGS) is already at work on a new analysis of how hard the ground is likely to shake and how close the rupture zone might come to urban areas the next time the Cascadia subduction zone really lets loose. The last time was in 1700, and the resulting quake was a magnitude-9 - just like the monster that struck Japan on March 11, 2010.

Japan's extensive network of seismometers, satellites, strain meters and GPS sensors logged a wealth of data that scientists continue to mine for insights.

"It's the best-recorded megaquake ever, and it's very relevant for the hazard in Cascadia," Anderson said.

Japanese scientists are struggling to answer several haunting questions: Why was the quake so big? How did the tsunami swell to such giant proportions? And why was it such a surprise to the world's most earthquake-savvy nation?

"It was very disheartening for people doing earthquake research and hazard mitigation in Japan," said Jim Mori, of Kyoto University's Disaster Prevention Research Institute.

Seismologists were fooled by a series of small quakes that rocked the area every 35 years or so, said Kenji Satake, of the University of Tokyo.

They believed each small quake relieved the pressure on the subduction zone - the boundary where two geologic plates slip past each other as the ocean floor shoves under the continent.

Now they realize strain continues to build until the series of small quakes is punctuated by a giant one about every 700 years. Similar quakes and tsunamis struck in the years 869 and 1896, but Japanese scientists failed to look far enough into their own history, Satake said. "We needed longer time records."

The longest record for a subduction zone is from Cascadia, where scientists have linked buried marshes and submarine landslides with a series of about 22 megaquake quakes going back 10,000 years. The time between quakes ranges from 200 to 1,000 years, with an average of about 500 years.

There's no obvious "supercyle" of supergiant quakes, as Satake suggests, in Japan. But it is clear that quakes on Cascadia have varied in size, said USGS scientist Brian Atwater. Some geologists argue the magnitude-9 quake 300 years ago was simply average and that the Northwest has been slammed by quakes twice as big in the distant past.

Most earthquake scenarios for the Northwest coast project tsunamis of about 30 feet, and scientists still don't know how much that needs to be ratcheted up post-Tohoku. Walls of water up to 120 feet high washed away entire communities on the Japanese coast.

Several of the yardsticks used to gauge the risk on subduction zones were proved questionable in Japan, he added.

Foremost among them is the measurement of strain buildup, as reflected by bulging and sinking land masses. Scientists had hoped they could identify fault segments that are about to snap - but the tension on the Japan subduction zone was not remarkable, Mori said.

Scientists are rethinking which subduction zones are most dangerous, said Kelin Wang, of the Geological Survey of Canada.

One emerging theory suggests seafloor topography might be key. Oceanic plates dotted with mountains seem to hang up and slip more frequently as they scrape under continental plates, he explained.

The result is a series of smaller quakes that occur when segments of the fault break. Giant quakes seem to occur most frequently where the seafloor is smooth and featureless - as off the Northwest coast, Wang said. With no surface bumps and hills to interfere, the two plates can stick together over vast distances, he said. When they slip, the whole fault breaks at once.

The nuclear-power industry around the world is still dealing with fallout from the meltdowns at Japan's Fukushima nuclear complex, said Stuart Nishenko, of Pacific Gas and Electric, which operates the Diablo Canyon nuclear plant on the California coast.

Seven nations, including Switzerland, Germany and Mexico, opted to either phase out nuclear power or halt construction of new plants. The U.S. Nuclear Regulatory Commission is preparing to issue orders to all of the nation's 104 nuclear reactors, requiring new seismic safety analyses, Nishenko said.

Operators also will be required to walk through their plants with inspectors, looking for any parts or systems vulnerable to earthquakes or floods, and to upgrade plans for coping with a complete loss of power, as happened when the Japanese tsunami knocked out electrical lines and flooded backup generators.

The Northwest's only nuclear power plant is the Columbia Generating Station, located on the Hanford Nuclear Reservation. In recent years, geologists have discovered several new faults running through the area, capable of generating earthquakes as big as magnitude 7.5. Plant operators recently applied for a license extension to operate the 28-year-old reactor though 2023.

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You got to love these kinds of sentences:"Scientists believed....Now they realize...."What a fool to think that we know even 1% there is to understand about earthquakes. We may believe something now, but that belief will surely be turned into another truth (or rather, belief) later on.

The only thing certain about earthquake predictions in the last 50 years is that we have not yet been able to predict any earthqakes. Period.

Yes, that's been a pet peeve of mine ever since childhood. Today, I could list chains of these believed/realized things where the next line would refer to the previous. Today, we live in the times of science fiction-come-true, and yet such Neanderthal thinking prevails.

In second grade I answered the question how many moons does Jupiter have, with "So far we have found 12 moons." The teacher blew her top. "Everybody knows Jupiter has exactly 12 moons!!!" She called my folks claiming I was a wise-ass.

This certainly gives one pause, to consider how devastating the March 11th events were for Tohoku.

I've always like saying that the history books are full of things that prior to them no one thought could or would happen, that's why they wrote about the extra-ordinary event - for future generations to know.

"Well, I'll be..." Sure its impossible to predict an earthquake. However, connecting the dots geographically, geothermically, and using your special thinking cap; all this would make me guess that these guys are right. There's gonna be a real big one on the Cascadian shores. Learn to duck and tumble, wear well padded clothes, and pack lots of ramen noodle packs in advance!

Earthquakes are examples of classic chaotic behaviour, we are not in a position to measure precise stresses upon tectonic plates going down hundreds of kilometers...

One thing for sure though, once you have improved instrumentation then the asymptote of predictability increases, all events are fundamentally probabilistic not deterministic as the vast majority of undisciplined 'creationists' would like us to believe and without evidence and without any construct of experimental processes.

A lot of the invective written about scientists is by journalists, just because someone believes doesn't necessarily make it true, like any in religion there are good and bad evangelists, rich or poor they have the same aim, similarly there are good and bad scientists BUT, the process of science has a mechanism of discipline - there is no such discipline in any religion, no peer reviewed process - only blind belief, no evidence and distinct lack of a deity's communication for 3700 years (or more) ..!

What a fool to think that we know even 1% there is to understand about earthquakes.

Do you believe this? Then you have just fallen into the same trap that you just decried.

"Scientists believed....Now they realize...."

That's how science works. We take the best models we have and use them - until data to the contrary arrives. Then the model is either refined or replaced. What else do you expect?If you want to see someone claim "This is infallibly right" then you need to go visit a church.

And don't equate the "Scientists believed..." with an untested/religious/gut belief. When scientists say they believe something then this means that all previous data seems to fit the model well enough and that this 'belief' is constantly being scrutinized and tested (via new data). For scientists 'belief' just equates to 'current working model'. Nothing more.

No, this is hierarchy, although priest might get disciplined (there's a joke somewhere) it's not a discipline per se' ie. Not in respect of acquiring more religious knowledge Eg precision to clarify any belief system - you cant have a discipline as the source of religion is static, Eg. Where was the discipline of why purgatory was abandoned ? Well, we had that then, we dont have it now, discipline for that please ?

Estavan57 admitted evolution.

Religions evolve as well as scientific belief.

How so, only static source, your deity doesn't update you guys - or does he/she/it, Purgatory how ?

Estevan57 lamented

I have never seen a black hole or electrons, but I still believe in them.

Neither I in detail but measurable, Eg W = V x I, and Eg. You cannot see metals, see light reflect off cloud of electrons, ie. U can see them and measure power easily.

Mike Massen "Estavan57 admitted evolution." Why would anyone not "admit" evolution? Finding an example of a mechanism of discipline in a religious organization contrary to your statement doesn't make me an anti-science zealot. Or a religious one. Perhaps not as much as you would want it to. :)

Religions evolve as well as scientific belief. They are very different and I was only responding to the statement of "no such discipline".

Please don't lump me into the box of "undisciplined 'creationists'", it just isn't me, I'm not one of those "you guys".The lack of accuracy in prediction of siesmic events or other chaotic events will frequently leave the opening for the "it's Gods will" remark. My usual response is "Just like evolution, it's Gods plan". I have had a lot of interesting discussions started from that one. Peace

Well gosh Estevan57 I must apologise, you are a rare beast indeed, an openly religious person who accepts evolutionary theory, does that also mean you accept the earth is some 4 billion years old & universe is around 13 billion years old ?

I am struck however with an apparent contradiction or perhaps its more a dichotomy where I cannot as yet see a bridge, your suggestion:-

"Religions evolve"

and

"Religions have a discipline"

I got the distinct impression because you see a hierarchy in religion you assume that's a discipline as if the less status opportuned are 'told off' etc. Obviously that cant be true.

So, what is the essential aspect of the discipline in Religion, is it in any way similar to the discipline in Science ?

How on earth does religion evolve, what is the mechanism ?

Which raises a more important question (for me), what is the Provenance of your position, on what does your belief rely as the core of an essential tenet ?

Mr Massen, after reviewing current Gallop Poll data on Belief in Evolution by religious and education levels, I just might be a rarity. I fall more in line with the "postgraduate" than the "weekly attendance" category.

I can only use the Catholic church as an example of a religion. Computer science, cad/cam and agronomy are more my thing.

The evolution of the church is one of more interpretation of doctrine both from the congregation "upward" to the Pope, as well as changes in interpretations of historical languages and historical documents. The order and form of the Mass, as the central expression of belief, has evolved accordingly. Examples: Not in Latin, music changes, congregational involvement, in local languages, and more. The peer review is in the form of conferences and meetings. It is the addition of new knowledge, but with an emphasis on getting the form and meaning of the central tenants correct. The meetings also address the needs of congregations and current issues.

There is discipline, but not the same as that used in science. It is by necessity hierarchial, due to the nature of the church, but there is some peer review and discussion. It doesn't meet the rigorous scientific review and addition of emperical data requirements of the scientific method, but it doesn't have to, it is a belief system, after all.

To sum my core belief, I would say this:

God made it, it's up to science to explain it. I really enjoy the advancement of communications so I can follow the changes.God, please spare me from your followers. ;)

I have no problem or discomfort with ANY scientific theory or fact. Except that "cold fusion thing". I am, however ashamed of an educational system that produces so few people that believe in evolution as the current theory. 39% in US, 79% in AUS though.

Cont. The official Catholic church defers to scientists MUCH more than it ever has. Some examples from Catholic Church and Evolution Wikipedia entry. Not the best entry but the sources are authentic.

"The Catechism of the Catholic Church (1994, revised 1997) on faith, evolution and science states: 159. Faith and science: "... methodical research in all branches of knowledge, provided it is carried out in a truly scientific manner and does not override moral laws, can never conflict with the faith, because the things of the world and the things of faith derive from the same God. The humble and persevering investigator of the secrets of nature is being led, as it were, by the hand of God in spite of himself, for it is God, the conserver of all things, who made them what they are."

Much more info in same wiki entry but space prohibits. To sum it up, the official Catholic church completely acknowledges the big bang theory, and evolution. Its position is causal, not mechanistic. Peace

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